This is an instrument for
making precise barometric pressure correction in laboratory operation. It is
also used in weather observation, Factories, Mines and Power plants.
The mercury level is
adjustable by means of knurled screws mounted at the bottom of the casing. When
the knurled screw is turned all the way into the casing mercury fulfills the
entire system and the tube accepts the very small volume to allow for thermal
to allow for thermal expansion. The barometer tube and scales covering the
glass are made from corning glass. The barometer is mounted on a polished
wooden board fitted with metal thermometer. Supplied without mercury.